# Copyright (c) Meta Platforms, Inc. and affiliates
import torch
from torch.distributed._tensor.op_schema import (
    OpSchema,
    OpStrategy,
    PlacementStrategy,
    StrategyType,
)
from torch.distributed._tensor.ops.utils import is_tensor_partial, register_op_strategy
from torch.distributed.device_mesh import DeviceMesh

aten = torch.ops.aten


@register_op_strategy(
    [aten.normal_.default, aten.uniform_.default, aten.native_dropout.default]
)
def random_op_strategy(mesh: DeviceMesh, op_schema: OpSchema) -> StrategyType:
    self_strategy = op_schema.args_schema[0]
    assert isinstance(self_strategy, OpStrategy)

    random_strategy = OpStrategy([])
    for arg_strategy in self_strategy.strategies:
        arg_spec = arg_strategy.out_spec
        if is_tensor_partial(arg_spec):
            # TODO: figure out how inplace random op should behave when it's partial
            raise RuntimeError(f"{op_schema.op} with _Partial is not supported yet!")
        random_strategy.strategies.append(PlacementStrategy(output_spec=arg_spec))

    return random_strategy
